Container lid



P 1965 w. A. FEAD ETAL 3,206,059-

CONTAINER LID Filed Sept. 13, 1962 Fig.2

INVENTORS William Alexander Feud BY Robert Myron Huff Gm 645 ,MAW/M? M01A TTORNEYS United States Patent "ce 3,206,059 CONTAINER LID William A.Fead, Plaintield, and Robert M. Haiti, Clark, N.J., assignors to HudsonPulp & Paper Corp, New York, N.Y., a corporation of Maine Filed Sept.13, 1962, Ser. No. 223,415 2 Claims. (Cl. 220-44) This invention relatesto container covers, and more in particular to a cover for a disposablepaper cup of the type used for hot and cold drinks and to thecombinations of such covers and cups.

An object of this invention is to provide an improved cover for hotdrink cups. A further object is to provide an improved lid whichprovides a spill-proof and slopproof cover for containers. A furtherobject is to provide for the above with a construction which is light inWeight, inexpensive to manufacture, and adaptable to various conditionsof use. These and other objects will be in part obvious and in partpointed out below.

In the drawings in which one embodiment of the invention shown:

FIGURE 1 is a top plan View of a lid installed on a paper cup;

FIGURE 2 is a side elevation of the cup and the lid of FIGURE 1; and,

FIGURE 3 is an enlarged sectional view on the line 3-3 of FIGURE 1.

Referring to the drawings, a lid 2 is installed on a paper cup 4 so asto form a thoroughly practical container for drinks such as hot coffee.Cup 4 has a tapered side wall 6 and at the top edge or lip (FIGURE 3)there is a bead 8. Lid 2 is formed from a thin sheet of fairly rigidplastic, and is generally disk shaped with a central vent dome 10 and aperipheral flange 12. Flange 12 snugly receives the beaded top of thecup and has an inner cylindrical wall 14 which engages the inner surfaceof the cup and an outer frusto-conical outer wall 16 which convergesdownwardly against the bead 8. An outwardly converging flange 18projects below wall 16 and may be engaged to remove the lid from thecup. Wall portions 14 and 16 are connected by a rounded portion 20 and aflat portion 22 which form two air spaces 24 and 26, respectively. Theseair spaces act to break a capillary passageway between the lid and cupwall surfaces and prevent migration of the liquid around the lip of thecup.

Vent dome 10 has a frusto-conical side wall and a flat upper wall 32 atthe center of which there is a vent opening 34. At the base of vent dome10 there is an annular rib 36 which is semi-circular in radial sectionand projects downwardly below the general plane of the body portion 38of the lid. There are also five radial ribs 40 and an outer annular rib42 which are of the same crosssection and project downwardly in the samemanner as rib 36. Each of the ribs 40 intersects rib 42, but they arespaced from rib 36 by a flat portion 44.

Vent 34 provides for the passage of air and vapor from and to the cupwhen the lid is being installed and removed. Furthermore, when the cupis used for a hot liquid such as hot coffee, vent 34 permits the escapeof water vapor and air so as to prevent an elevated pressure conditionwithin the cup; and, if the liquid becomes cooled, vent 34 prevents thecreation of sub-atmospheric pressure which would interfere with theremoval of the lid.

3,206,059 Patented Sept. 14, 1965 Lid 2 is splash-proof or slop-proof inthat liquid does not splash or seep out during normal handling of thecup with the lid installed. It has been found that such spilling ofliquid results from wave motion on the surface of the liquid. With priorcovers having vent openings, the wave motion produced liquid pressurewhich projected liquid to the vent opening and even spurted out onto thetop of the lid. The formation of vapor from hot liquid also causesliquid in the vent opening to seep out. However, the rib construction inlid 2 breaks up the surface Waves and diverts them from the dome 10 andvent opening 34. Dome 10 and rib 36 act as an effective means to preventthe passage of liquid through vent opening 34 during normal usage. Ribs40 and 42 act to minimize the surface wave motion and tend to directwaves radially so that they are dampened. Ribs 40 and 42 also impartphysical strength to the lid.

It is thus seen that the lid 2 provides a thoroughly satisfactory coverfor containers, and has particular advantages with hot liquids. The lidmay be installed easily and it has been found that hot coffee and thelike will not leak from the outer rim or from the vent opening duringnormal usage. The vent opening 34 is maintained free of liquid underconditions of use which would cause considerable leakage with priorconstructions. It has been indicated above that lid 2 is formed ofplastic and illustratively this is polystyrene, the original sheet being.0105 inch in thickness. It will be appreciated that other materialssuch as water-proofed paper may be used and that the thickness of thematerial and lid size may be varied without departing from theinvention.

What is claimed is:

1. A lid for a paper cup or the like having a bead surrounding a topopening, said lid'comprising an integral sheet structure having aperipherial flange portion which snugly receives the bead on the cup andforms a seal therewith and a substantially central dome portion which issubstantially frusto-conical and which projects upward- 1y when the lidis positioned upon the cup and has a top wall with a vent openingtherewith, said lid also including downwardly-projecting rib portionscomprising an annular rib portion surrounding said dome portion and aplurality of radial rib portions which extend between said annular ribportions and said flange portion and which are spaced therefrom at theirrespective ends, whereby said radial rib portions tend to direct thesurface of the liquid within the cup radially and said radial ribportions cooperate with said annular rib portions to break up the wavemotion in the liquid and prevent the moving liquid from projecting intosaid dome portion against said vent opening.

2. A lid construction as described in claim 1 which is formed from asheet of polystyrene or the like having an original thickness of theorder of .0105 inch.

References Cited by the Examiner UNITED STATES PATENTS 1,591,142 7/26Reeves 22044 2,693,307 11/54 Goodwin 229-43 2,726,517 12/55 Pruett.

3,048,317 8/62 Cochrane 220-44 THERON E. CONDON, Primary Examiner.

EARLE J. DRUMMOND, Examiner.

1. A LID FOR A PAPER CUP OR THE LIKE HAVING A BEAD SURROUNDING A TOPOPENING, SAID LID COMPRISING AN INTEGRAL SHEET STRUCTURE HAVING APERIPHERAL FLANGE PORTION WHICH SNUGLY RECEIVES THE BEAD ON THE CUP ANDFORMS A SEAL THEREWITH AND A SUBSTANTIALLY CENTRAL DOME PORTION WHICH ISSUBSTANTIALLY FRUSTO-CONICAL AND WHICH PROJECTS UPWARDLY WHEN THE LID ISPOSITIONED UPON THE CUP AND HAS A TOP WALL WITH A VENT OPENINGTHEREWITH, SAID LID ALSO INCLUDING DOWNWARDLY-PROJECTING RIB PORTIONSCOMPRISING AN ANNULAR RIB PORTION SURROUNDING SAID DOME PORTION AND APLURALITY OF RADIAL RIB PORTION WHICH EXTEND BETWEEN SAID ANNULAR RIBPORTIONS AND SAID FLANGE PORTION AND WHICH ARE SPACED THEREFROM AT THEIRRESPECTIVE ENDS, WHEREBY SAID RADIAL RIB PORTIONS TEND TO DIRECT THESURFACE OF THE LIQUID WITHIN THE CUP RADIALLY AND SAID RADIAL RIBPORTIONS COOPERATE WITH SAID ANNULAR RIB PORTIONS TO BREAK UP THE WAVEMOTION IN THE LIQUID AND PREVENT THE MOVING LIQUID FROM PROJECTING INTOSAID DOME PORTION AGAINST SAID VENT OPENING.